The Cameron Safety Self filler fountain pen appears to be a basic bulb filler pen. However, the sac is full length of the pen, extending to the section, and serves as the ink reservoir (unlike the barrel reservoir of a traditional bulb filler). It adds bars on either side of the bulb to add a touch of class as well as improved sac compression ability to an otherwise simple filling system. The narrower bar runs the full length of the barrel. The wide bar is shorter, but gives the user leverage to compress the full length of the sac with the longer bar. Todd Merrell in the Facebook group said it is a “proto-Aerometric” and I have to agree!